Hey Lauri (again, mailing list in Cc to make mentoring public),

Here are the problems I had when compiling on Windows (except for the Visual Studio project not being up to date with the new files of course):
- use of fmaxf() instead (std::max<float>() is ok, include <algorithm>)
- IrrCompileConfig.h configured to use the system libraries
- callbacks.c from enet and callback.cpp from your modifications conflict as they generate the same .obj with Visual Studio (we should change the project configuration)
- and of course I had to add the Visual Studio projects, dependencies and Irrlicht embedded dependencies sources

Launching the game leads to a crash with this callstack:
>    supertuxkart_d.exe!irr::video::COpenGLExtensionHandler::extGlCheckFramebufferStatus(unsigned int target) Line 1992    C++
     supertuxkart_d.exe!irr::video::checkFBOStatus(irr::video::COpenGLDriver * Driver) Line 905    C++
     supertuxkart_d.exe!irr::video::COpenGLFBODepthTexture::attach(irr::video::ITexture * renderTex) Line 873    C++
     supertuxkart_d.exe!irr::video::COpenGLDriver::addRenderTargetTexture(const irr::core::dimension2d<unsigned int> & size, const irr::core::string<char,irr::core::irrAllocator<char> > & name, const irr::video::ECOLOR_FORMAT format, const bool useStencil) Line 4016    C++
     supertuxkart_d.exe!rtt_t::rtt_t() Line 34    C++
     supertuxkart_d.exe!IrrDriver::initDevice() Line 408    C++
     supertuxkart_d.exe!initRest() Line 1139    C++
     supertuxkart_d.exe!main(int argc, char * * argv) Line 1314    C++

I will investigate later, I need to go to sleep now ^^.

Ah BTW, the names rtt_t and e_rtt_t don't follow our CamelCase convention :)
And please try to avoid including headers when not necessary (#include <ITexture.h> in rtts.hpp), the compilation time is already a bit long...

On bloom/glow/outline: with light prepass, if you plan to separate diffuse and specular lighting, maybe you could use the specular buffer to blur it and select where the glow effect would be? As we said on IRC, specular exponent could go in alpha channel if we don't want to add a specular texture.
What do you think?